World first MRI study sheds light on heart damage during kidney dialysis

Experts in magnetic resonance imaging (MRI) and kidney disease have carried out the first ever scans to study the heart function of kidney patients while they are having dialysis treatment.

People with kidney failure need regular dialysis to remove fluid and waste products from their blood, but this process can cause falls in blood pressure and reduced blood flow to the heart. Over time this can cause long-term damage to the heart.

Research at The University of Nottingham was undertaken to investigate stress on the heart during kidney dialysis and to compare two different types of dialysis in this regard: standard haemodialysis (HD) and hemodiafiltration (HDF), a process that removes more fluid during treatment but with additional replacement fluid being given to the patient.

Experts from the University's Sir Peter Mansfield Imaging Centre (SPMIC) and the Centre for Kidney Research and Innovation (CKRI) carried out MRI scans on 12 kidney dialysis patients who were each allocated to receive both standard haemodialysis (HD) and HDF in a random order.

The study found significant cardiovascular effects with both standard haemodialysis and HDF, but no differences between the two. Results demonstrate that cardiac MRI can be a vital tool for evaluating future improvements to dialysis treatment.

Professor of Physics, Sue Francis, said: "This is the first time that MRI has been used to look at heart function while the kidney patient is actually undergoing dialysis. There were several hurdles to overcome to achieve this. We had to set up a dialysis machine in our MRI research centre, change the metal needles that go into the patient to non-magnetic silicone ones, extend and insulate the lines that connect the patient to the dialysis machine and position the equipment using our knowledge of the magnetic fields in the MRI unit."

Professor of Medicine (Nephrology), Maarten Taal, said: "Using this unique set-up we were able to monitor multiple cardiovascular measurements while dialysis was taking place in the patients. We measured how many litres of blood were pumped per minute by the left ventricle of the heart, how well the heart muscle was able to contract, blood flow in the coronary artery which supplies the heart muscle and myocardial perfusion to check the efficiency of blood flow to the capillaries or tiny blood vessels in the heart muscle."

"Interestingly, we found all measures of systolic contractile function fell during both standard haemodialysis and haemodiafiltration with partial recovery after dialysis. All patients showed some degree of left ventricular dysfunction and blood flow to the small capillaries in the heart muscle decreased significantly during both types of treatment. Our observations confirm the need for interventions to reduce the negative impact of dialysis on the heart."

Having successfully tested this method, the research team is now aiming to test the effects of other dialysis treatments using MRI.

Intradialytic Cardiac Magnetic Resonance Imaging to Assess Cardiovascular Responses in a Short-Term Trial of Hemodiafiltration and Hemodialysis is published in the Journal of the American Society of Nephrology (JASN).

-end-

Our academics can now be interviewed for broadcast via our Media Hub, which offers a Globelynx fixed camera and ISDN line facilities at University Park campus. For further information please contact a member of the Communications team on +44 (0)115 951 5798, email mediahub@nottingham.ac.uk or see the Globelynx website for how to register for this service.

For up to the minute media alerts, follow us on Twitter

Notes to editors: The University of Nottingham has 43,000 students and is 'the nearest Britain has to a truly global university, with a "distinct" approach to internationalisation, which rests on those full-scale campuses in China and Malaysia, as well as a large presence in its home city.' (Times Good University Guide 2016). It is also one of the most popular universities in the UK among graduate employers and the winner of 'Outstanding Support for Early Career Researchers' at the Times Higher Education Awards 2015. More than 97% of research at The University of Nottingham is recognised internationally and it is 8th in the UK by research power according to the Research Excellence Framework 2014. It has been voted the world's greenest campus for four years running, according to Greenmetrics Ranking of World Universities.

Impact: The Nottingham Campaign, its biggest-ever fundraising campaign, is delivering the University's vision to change lives, tackle global issues and shape the future. More news...

Forging new defenses against diabetic kidney diseaseScientists at Joslin Diabetes Center have revealed an unexpected route to slow the progression of diabetic kidney disease, targeting a biological pathway that is the main channel for the metabolism of glucose in the cell.

A kidney disease's genetic clues are uncoveredResearchers at Columbia University Medical Center have identified genes that are linked to the underlying molecular defect in people with IgA nephropathy, an autoimmune kidney disease.

#514 Arctic Energy (Rebroadcast)This week we're looking at how alternative energy works in the arctic. We speak to Louie Azzolini and Linda Todd from the Arctic Energy Alliance, a non-profit helping communities reduce their energy usage and transition to more affordable and sustainable forms of energy. And the lessons they're learning along the way can help those of us further south.